<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>demo13</title>
    <style>
        /*div {
            width: 400px;
            height: 200px;
            /* border-style: solid;
            border-color: green;
            border-width: 5px; */
            /* 上述简写 */
            /*border: 5px solid green;
            /* 使边框带有圆角效果 */
            /*border-radius: 10px;
        }*/


        /*div {
            /* width: 200px;
            height: 100px;
            border: 5px solid green; */
            /* 使边框带有圆角效果 */
            /* border-radius: 50px; */
            /* 通过 box-sizing 属性可以修改浏览器的行为, 使边框不再撑大盒子 */
            /* box-sizing: border-box; */

            /* radius为width的一半就是圆，height要和width相等 */
            /* width: 200px;
            height: 200px;
            border: 5px solid green;
            border-radius: 100px; */

            /* height: 300px;
            width: 200;
            
            /* padding-left: 10px;
            padding-top: 5px; */
            
            /* 或者通过顺时针的方式设置上右下左 */
            /*padding: 10px 5px 10px 5px; */

            /*height: 200px;
            width: 200px;*/
            /* background-color: red; */
            /* margin-bottom: 20px; */

            /* 居中 */
            /* margin: auto; */

            /* 去除浏览器默认样式 */
           /* margin: 0;
            padding: 0;*/
      /*  }*/

      div {
        width: 100%;
        height: 150px;
        background-color: red;

        /* 弹性布局 */
        display: flex;

        /* justify-content: space-between; */

      }

      div>span {
        background-color: green;
        width: 100px;
        height: 100px;
      }
        
    </style>
</head>
<body>
    <!-- <div>padding</div> -->
    <!-- <div>margin</div> -->

    <div>
        <span>1</span>
        <span>2</span>
        <span>3</span>

    </div>
</body>
</html>